This would use Hero Slimer (I made one, and I CZ was thinking about doing a PDF Hero Slimer from RGB cartoon). I also made food tokens, but they are just 1" circles with Clip Art of food items.

Set out 5-10 food pieces randomly. Put Slimer on the board, and Hero Slimer at opposite ends. Slimer wants to eat the food, as does Hero Slimer. For regular "Evil" Slimer, treat food as Slime tokens. Hero Slimer has his own effects for food. Have 1-8 Galloping Ghouls in the Spirit world or use Wadey's random cards to add a challenge. The GB's need to stop the random ghosts like usual, and Slimer.Hero Slimer hurts/helps the Busters. If Hero Slimer gets more food than Slimer, you win. If Slimer gets more of the food, you lose.

PEOPLEBUSTERS
Class 3To Hit: 4 or higher.To Trap: 3 streams.When Hit: Add a stream token to a Peoplebuster.When Missed: The Peoplebuster moves 2 spaces in the direction of the nearest Ghostbuster.Special: Peoplebusters can fire Slime at Ghostbusters within 3 spaces. Peoplebusters hit on a roll of four or greater. If a Ghostbuster has more than two Slime tokens from a Peoplebuster, they can't move. You can spend actions to remove the slime on their turn.